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bioRxiv · 10.64898/2026.09.11.750917

DepoCat: Interactive database of experimentally verified phage depolymerases

Olejniczak, S.·Otwinowska, A.·Pozniak, M.·Drulis-Kawa, Z.
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Abstract

Klebsiella phage depolymerases degrade polysaccharide capsules and exhibit narrow substrate specificity for particular capsular types. Despite a growing number of experimentally characterized enzymes, these data remain scattered throughout the scientific literature, while existing protein sequence repositories are dominated by entries with computationally assigned, unverified functional annotations. Here we present DepoCat, the first interactive database of phage depolymerases with experimentally verified function and specificity, available at http://depocat.uwr.edu.pl. The database currently contains 131 proteins meeting rigorous inclusion criteria, spanning 75 distinct capsular types. Each entry integrates experimental and computational resources. The web interface provides an integrated Classifier tool with two search modes: sequence-based search and structure-based search - enabling preliminary structural classification and inference of putative substrate specificity of newly identified depolymerases. We demonstrated the utility of both modes on a set of 17 experimentally verified non-Klebsiella phage depolymerases, for which structural analysis enabled unambiguous class assignment in almost all cases despite low or undetectable sequence similarity to the database reference dataset. DepoCat constitutes a publicly accessible resource supporting research into the structural diversity and sequence-structure-specificity relationships of phage depolymerases, while also facilitating the identification of candidates for therapeutic and diagnostic applications.

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Olejniczak, S., Otwinowska, A., Pozniak, M., Drulis-Kawa, Z.. 2026-09-17. DepoCat: Interactive database of experimentally verified phage depolymerases. https://doi.org/10.64898/2026.09.11.750917

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